1. FIELD OF THE INVENTION
This invention relates to a semiconductor integrated circuit device and, more particularly, to a semiconductor device having a plurality of semiconductor integrated circuit blocks disposed close to each other.
2. DESCRIPTION OF THE RELATED ART
FIG. 12 is a sectional view of an essential portion of a semiconductor integrated circuit device of this kind. A digital circuit block 1 and an analog circuit block 2 are formed as semiconductor integrated circuit blocks on a substrate 10 formed of a semiconductor or an insulating material. These circuit blocks 1 and 2 are disposed with a spacing L provided therebetween. An insulating layer 20 is formed on the substrate 10 so as to cover the circuit blocks 1 and 2. The circuit blocks 1 and 2 are thereby insulated from each other.
Because the plurality of semiconductor blocks 1 and 2 are disposed close to each other with a portion of the insulating layer 20 interposed therebetween, there is a possibility that noise such as clock noise or switching noise caused, for example, in the digital circuit block 1 is transmitted to the analog circuit block 2 through a parasitic capacitance formed through insulating layer 20 so that the performance of the semiconductor integrated circuit device is deteriorated.
Increasing the spacing L between the circuit blocks 1 and 2 may be considered as a means for preventing this problem. However, the degree of integration of circuit blocks in the semiconductor integrated circuit device is thereby reduced.